پديد آورندگان :
احمدي, محسن دانشگاه صنعتي نوشيرواني بابل - دانشكده ي مهندسي عمران , نقي پور, مرتضي دانشگاه صنعتي نوشيرواني بابل - دانشكده ي مهندسي عمران , نعمت زاده, مهدي دانشگاه مازندران - دانشكده ي مهندسي عمران
كليدواژه :
ستون مركب , SRC , ظرفيت باربري , بار خارج از مركز
چكيده فارسي :
ستون هاي بتني مسلح شده با فولاد (SRC) نوعي از ستون هاي مركب هستند كه به دليل مزاياي فراواني كه نسبت به ستون هاي بتن آرمه و ستون هاي فقط فولادي دارند، استفاده از آن ها رواج زيادي پيدا كرده است. در پژوهش حاضر، جهت بررسي برخي از عوامل موثر در ظرفيت باربري ستون هاي بتني مسلح شده با فولاد(SRC) تحت بار خارج از مركز، يك مطالعه ي عددي با نرم افزار آباكوس انجام و مدل المان محدود ايجاد شده و با نتايج آزمايشگاهي اعتبارسنجي شده است. در مجموع 39 ستون براي مطالعه ي پارامتريك تحليل شدند كه متغيرهاي هندسي و مصالح از قبيل: درصد فولاد، نسبت لاغري ستون، نسبت خروج از مركزيت نيرو، مقاومت فشاري بتن و فاصله ي ميلگردهاي عرضي در ظرفيت باربري ستون ها بررسي شدند و براساس مقادير محاسبه شده، نمودارهاي نيرو تغييرمكان محوري، نيرو تغييرمكان جانبي، و نيرو -لنگرخمشي ترسيم شدند، به طوري كه با افزايش درصد فولاد و كاهش فاصله بين ميلگردهاي عرضي، شاخص شكل پذيري افزايش يافته است، اما با كاهش فاصله بين ميلگردهاي عرضي، ظرفيت باربري ستون به صورت جزيي افزايش يافته است.
چكيده لاتين :
Due to the numerous advantages of Steel Reinforced Concrete (SRC) as a kind of composite columns over the reinforced concrete and steel columns, its use has been widespread in recent years, especially in high-rise buildings. In these columns, due to the presence of steel profiles in the reinforced concrete, the buckling of the steel components is delayed or does not occur, which would significantly increase the bearing capacity of the cross-section. In this research, a numerical study was carried out with the aid of ABAQUS software to investigate some of the factors affecting the load capacity of SRC columns under eccentric loading. A finite element model was validated based on experimental results. A total of 39 SRC columns were analyzed for parametric study. Geometric and material variables such as steel ratio, slenderness column ratio, eccentric loading ratio, compressive strength, and stirrup spacing were evaluated on the bearing capacity of the SRC columns. Also, based on the calculated values, the axial and lateral load-displacement as well as axial load-bending moment curves were plotted. The results showed that with increase in the steel ratio and the reduction of the distance between the stirrups, the ductility index increased, while with the reduction of the distance between the stirrups, the bearing capacity of the column increased slightly. Moreover, with the increase of the eccentricity, the bearing capacity of the columns was significantly reduced and the slope of the descending branch of lateral load-displacement decreased gradually. Moreover, if the column was less slender, the axial load-displacement curve would have a greater initial slope and with increasing slenderness, the lateral load-displacement would have more nonlinear behavior due to increased second-order deformation. In addition, the axial load and stiffness of the composite column were significantly affected by the concrete compressive strength. The results also indicated that with increasing the eccentricity, the bearing capacity of the composite columns was reduced.
